1: dibal / diethyl ether / -78 - 0 °C 2: TEA, DMAP / CH2Cl2 3: 48percent aq. HF / acetonitrile / 0 °C 4: 81 percent / NaHCO3, I2 / CH2Cl2 / 1.5 h / 0 °C View Scheme

1: dibal / diethyl ether / -78 - 0 °C 2: TEA, DMAP / CH2Cl2 3: 48percent aq. HF / acetonitrile / 0 °C 4: 81 percent / NaHCO3, I2 / CH2Cl2 / 1.5 h / 0 °C 5: 54 percent / 1.) AgBF4, 2.) H2O / 48 h / 21 °C View Scheme

diisobutylaluminium hydride in diethyl ether T=-78 - 0°C; Yield given;

diisobutylaluminium hydride in diethyl ether T=-78 - 0°C; Yield given;

1: dibal / diethyl ether / -78 - 0 °C 2: TEA, DMAP / CH2Cl2 View Scheme

<b>Multi-step reaction with 3 steps<br /> </b>1: 75 percent / TEA,DMAP / tetrahydrofuran; dimethylformamide / Heating<br />2: 1.) O₃, 2.) Me₂S / 1.) MeOH, - 60 deg C<br />3: 56 percent / KN(Me₄Si)2, 18-C-6 / tetrahydrofuran<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: 1.) CuI / 1.) Et₂O<br />2: 75 percent / TEA,DMAP / tetrahydrofuran; dimethylformamide / Heating<br />3: 1.) O₃, 2.) Me₂S / 1.) MeOH, - 60 deg C<br />4: 56 percent / KN(Me₄Si)2, 18-C-6 / tetrahydrofuran<br /> <br /> &nbsp;